Update flake template

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

hosts/common/configs/user/console/nix-develop/template.nix

@@ -1,42 +1,33 @@
 {
   inputs = {
-    nixpkgs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
-      type = "github";
-      owner = "karaolidis";
-      repo = "nixpkgs";
-      ref = "integration";
-    };
 
-    flake-utils = {
+    flake-utils.url = "github:numtide/flake-utils";
-      type = "github";
-      owner = "numtide";
-      repo = "flake-utils";
-      ref = "main";
-    };
 
     treefmt-nix = {
-      type = "github";
+      url = "github:numtide/treefmt-nix";
-      owner = "numtide";
-      repo = "treefmt-nix";
-      ref = "main";
-
       inputs.nixpkgs.follows = "nixpkgs";
     };
   };
 
   outputs =
-    { self, nixpkgs, ... }@inputs:
+    inputs:
-    inputs.flake-utils.lib.eachDefaultSystem (
+    (
-      system:
       let
-        pkgs = nixpkgs.legacyPackages.${system};
+        system = "x86_64-linux";
+
+        pkgs = import inputs.nixpkgs {
+          inherit system;
+          config.allowUnfree = true;
+        };
+
         treefmt = inputs.treefmt-nix.lib.evalModule pkgs ./treefmt.nix;
       in
       {
-        devShells.default = pkgs.mkShell { packages = with pkgs; [ ]; };
+        devShells.${system}.default = pkgs.mkShell { packages = with pkgs; [ ]; };
 
-        formatter = treefmt.config.build.wrapper;
+        formatter.${system} = treefmt.config.build.wrapper;
-        checks.formatting = treefmt.config.build.check self;
+        checks.formatting.${system} = treefmt.config.build.check inputs.self;
       }
     );
 }